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Albert Einstein’s Sci-Fi Stories

• ant6n 11y ago
  "By the time (...) in 1846, it was well known that light had a finite speed. Ole Rømer, a Danish scientist working in Paris, had proved as much more than a century and a half earlier." I found this intriguing, how did he measure it? Well it turns out Romer wanted to create an absolute clock that could be used in navigation -- the clock being the orbit of Io around Jupiter, whose orbital period is a bit less than 2 days. They figured that if they had exact tables into the future, you could get the absolute time anywhere on earth, and thus estimate your longitude. Romer found that during the seasons, the orbit moved 11 minutes ahead, then 11 minutes behind relative to the mean predicted orbit. He figured that this is due to the finite speed of light; and if you know the measure of an AU you get that c = 2*AU/22min. source: http://www.amnh.org/education/resources/rfl/web/essaybooks/cosmic/p_roemer.html http://www.amnh.org/education/resources/rfl/web/essaybooks/c...
  • deleted 11y ago
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